Better flowing column support

openhtmltopdf-core/src/main/java/com/openhtmltopdf/css/constants/CSSName.java

@@ -20,10 +20,10 @@
  */
 package com.openhtmltopdf.css.constants;
 
+import java.util.HashMap;
 import java.util.Iterator;
 import java.util.Map;
-import java.util.TreeMap;
-
+import java.util.Objects;
 import com.openhtmltopdf.css.parser.CSSErrorHandler;
 import com.openhtmltopdf.css.parser.CSSParser;
 import com.openhtmltopdf.css.parser.PropertyValue;
@@ -55,7 +55,7 @@
  *
  * @author Patrick Wright
  */
-public final class CSSName implements Comparable {
+public final class CSSName implements Comparable<CSSName> {
     /**
      * marker var, used for initialization
      */
@@ -115,12 +115,12 @@ public final class CSSName implements Comparable {
     /**
      * Map of all CSS properties
      */
-    private static final Map ALL_PROPERTY_NAMES = new TreeMap();
+    private static final Map<String, CSSName> ALL_PROPERTY_NAMES = new HashMap<>();
 
     /**
      * Map of all non-shorthand CSS properties
      */
-    private static final Map ALL_PRIMITIVE_PROPERTY_NAMES = new TreeMap();
+    private static final Map<String, CSSName> ALL_PRIMITIVE_PROPERTY_NAMES = new HashMap<>();
 
     /**
      * Unique CSSName instance for CSS2 property.
@@ -915,6 +915,24 @@ public final class CSSName implements Comparable {
                     INHERITS,
                     new PrimitivePropertyBuilders.PageBreakInside()
             );
+
+    public final static CSSName BREAK_AFTER =
+            addProperty(
+                    "break-after",
+                    PRIMITIVE,
+                    "auto",
+                    NOT_INHERITED,
+                    new PrimitivePropertyBuilders.BreakAfter()
+            );
+
+    public final static CSSName BREAK_BEFORE =
+            addProperty(
+                    "break-before",
+                    PRIMITIVE,
+                    "auto",
+                    NOT_INHERITED,
+                    new PrimitivePropertyBuilders.BreakBefore()
+            );
 
     /**
      * Unique CSSName instance for CSS2 property.
@@ -1815,24 +1833,6 @@ public static int countCSSPrimitiveNames() {
         return ALL_PRIMITIVE_PROPERTY_NAMES.size();
     }
 
-    /**
-     * Iterator of ALL CSS 2 visual property names.
-     *
-     * @return Returns
-     */
-    public static Iterator allCSS2PropertyNames() {
-        return ALL_PROPERTY_NAMES.keySet().iterator();
-    }
-
-    /**
-     * Iterator of ALL primitive (non-shorthand) CSS 2 visual property names.
-     *
-     * @return Returns
-     */
-    public static Iterator allCSS2PrimitivePropertyNames() {
-        return ALL_PRIMITIVE_PROPERTY_NAMES.keySet().iterator();
-    }
-
     /**
      * Returns true if the named property inherits by default, according to the
      * CSS2 spec.
@@ -1877,8 +1877,7 @@ public static PropertyBuilder getPropertyBuilder(CSSName cssName) {
      * @return The byPropertyName value
      */
     public static CSSName getByPropertyName(String propName) {
-
-        return (CSSName) ALL_PROPERTY_NAMES.get(propName);
+        return ALL_PROPERTY_NAMES.get(propName);
     }
 
     public static CSSName getByID(int id) {
@@ -1927,10 +1926,10 @@ private static synchronized CSSName addProperty(
     }
 
     static {
-        Iterator iter = ALL_PROPERTY_NAMES.values().iterator();
+        Iterator<CSSName> iter = ALL_PROPERTY_NAMES.values().iterator();
         ALL_PROPERTIES = new CSSName[ALL_PROPERTY_NAMES.size()];
         while (iter.hasNext()) {
-            CSSName name = (CSSName) iter.next();
+            CSSName name = iter.next();
             ALL_PROPERTIES[name.FS_ID] = name;
         }
     }
@@ -1941,8 +1940,8 @@ public void error(String uri, String message) {
                 XRLog.cssParse("(" + uri + ") " + message);
             }
         });
-        for (Iterator i = ALL_PRIMITIVE_PROPERTY_NAMES.values().iterator(); i.hasNext(); ) {
-            CSSName cssName = (CSSName)i.next();
+        for (Iterator<CSSName> i = ALL_PRIMITIVE_PROPERTY_NAMES.values().iterator(); i.hasNext(); ) {
+            CSSName cssName = i.next();
             if (cssName.initialValue.charAt(0) != '=' && cssName.implemented) {
                 PropertyValue value = parser.parsePropertyValue(
                         cssName, StylesheetInfo.USER_AGENT, cssName.initialValue);
@@ -1959,14 +1958,14 @@ public void error(String uri, String message) {
         }
     }
 
-    //Assumed to be consistent with equals because CSSName is in essence an enum
-    public int compareTo(Object object) {
-        if (object == null) throw new NullPointerException();//required by Comparable
-        return FS_ID - ((CSSName) object).FS_ID;//will throw ClassCastException according to Comparable if not a CSSName
+    // Assumed to be consistent with equals because CSSName is in essence an enum
+    @Override
+    public int compareTo(CSSName object) {
+        Objects.requireNonNull(object);
+        return this.FS_ID - object.FS_ID;
     }
 
-    // FIXME equals, hashcode
-
+    @Override
     public boolean equals(Object o) {
         if (this == o) return true;
         if (!(o instanceof CSSName)) return false;
@@ -1976,6 +1975,7 @@ public boolean equals(Object o) {
         return FS_ID == cssName.FS_ID;
     }
 
+    @Override
     public int hashCode() {
         return FS_ID;
     }

openhtmltopdf-core/src/main/java/com/openhtmltopdf/css/constants/IdentValue.java

@@ -54,12 +54,9 @@
  */
 public class IdentValue implements FSDerivedValue {
     private static int maxAssigned = 0;
+    private static final Map<String, IdentValue> ALL_IDENT_VALUES = new HashMap<>();
 
-    /**
-     * Description of the Field
-     */
     private final String ident;
-
     public final int FS_ID;
 
     public final static IdentValue ABSOLUTE = addValue("absolute");
@@ -254,11 +251,10 @@ public class IdentValue implements FSDerivedValue {
     public static final IdentValue BORDER_BOX = addValue("border-box");
     public static final IdentValue CONTENT_BOX = addValue("content-box");
 
-
-    /**
-     * Description of the Field
+    /*
+     * Column break. 
      */
-    private static Map<String, IdentValue> ALL_IDENT_VALUES;
+    public static final IdentValue COLUMN = addValue("column");
 
     /**
      * Constructor for the IdentValue object
@@ -276,6 +272,7 @@ private IdentValue(String ident) {
      *
      * @return a string representation of the object.
      */
+    @Override
     public String toString() {
         return ident;
     }
@@ -290,22 +287,19 @@ public String toString() {
      * @return see desc.
      */
     public static IdentValue getByIdentString(String ident) {
-        IdentValue val = (IdentValue) ALL_IDENT_VALUES.get(ident);
+        IdentValue val = ALL_IDENT_VALUES.get(ident);
         if (val == null) {
             throw new XRRuntimeException("Ident named " + ident + " has no IdentValue instance assigned to it.");
         }
         return val;
     }
 
-    /**
-     * TODO: doc
-     */
     public static boolean looksLikeIdent(String ident) {
-        return (IdentValue) ALL_IDENT_VALUES.get(ident) != null;
+        return ALL_IDENT_VALUES.get(ident) != null;
     }
 
     public static IdentValue valueOf(String ident) {
-        return (IdentValue)ALL_IDENT_VALUES.get(ident);
+        return ALL_IDENT_VALUES.get(ident);
     }
 
     public static int getIdentCount() {
@@ -318,10 +312,7 @@ public static int getIdentCount() {
      * @param ident The feature to be added to the Value attribute
      * @return Returns
      */
-    private final static synchronized IdentValue addValue(String ident) {
-        if (ALL_IDENT_VALUES == null) {
-            ALL_IDENT_VALUES = new HashMap<String, IdentValue>();
-        }
+    private final static IdentValue addValue(String ident) {
         IdentValue val = new IdentValue(ident);
         ALL_IDENT_VALUES.put(ident, val);
         return val;

openhtmltopdf-core/src/main/java/com/openhtmltopdf/css/parser/property/PrimitivePropertyBuilders.java

@@ -1303,7 +1303,25 @@ protected BitSet getAllowed() {
             return ALLOWED;
         }
     }
+
+    public static class BreakBefore extends SingleIdent {
+        private static final BitSet ALLOWED = setFor(
+                new IdentValue[] { IdentValue.AUTO, IdentValue.COLUMN });
+
+        protected BitSet getAllowed() {
+            return ALLOWED;
+        }
+    }
 
+    public static class BreakAfter extends SingleIdent {
+        private static final BitSet ALLOWED = setFor(
+                new IdentValue[] { IdentValue.AUTO, IdentValue.COLUMN });
+
+        protected BitSet getAllowed() {
+            return ALLOWED;
+        }
+    }
+
     public static class Page extends AbstractPropertyBuilder {
         public List buildDeclarations(
                 CSSName cssName, List values, int origin, boolean important, boolean inheritAllowed) {

openhtmltopdf-core/src/main/java/com/openhtmltopdf/css/style/CalculatedStyle.java

@@ -943,6 +943,10 @@ public boolean isAutoZIndex() {
     }
 
     public boolean establishesBFC() {
+        if (hasColumns()) {
+            return true;
+        }
+
         FSDerivedValue value = valueByName(CSSName.POSITION);
 
         if (value instanceof FunctionValue) {  // running(header)
@@ -1031,7 +1035,7 @@ public boolean isListItem() {
     }
 
     public boolean hasColumns() {
-    	return !isIdent(CSSName.COLUMN_COUNT, IdentValue.AUTO) && asFloat(CSSName.COLUMN_COUNT) > 1;
+        return !isIdent(CSSName.COLUMN_COUNT, IdentValue.AUTO) && asFloat(CSSName.COLUMN_COUNT) > 1;
     }
 
     public int columnCount() {
@@ -1091,6 +1095,14 @@ public boolean isForcePageBreakAfter() {
         return val == IdentValue.ALWAYS || val == IdentValue.LEFT
                 || val == IdentValue.RIGHT;
     }
+
+    public boolean isColumnBreakBefore() {
+        return isIdent(CSSName.BREAK_BEFORE, IdentValue.COLUMN);
+    }
+
+    public boolean isColumnBreakAfter() {
+        return isIdent(CSSName.BREAK_AFTER, IdentValue.COLUMN);
+    }
 
     public boolean isAvoidPageBreakInside() {
         return isIdent(CSSName.PAGE_BREAK_INSIDE, IdentValue.AVOID);

openhtmltopdf-core/src/main/java/com/openhtmltopdf/layout/BoxBuilder.java

@@ -1154,7 +1154,7 @@ private static void createChildren(
                         child.setElement(element);
 
                         if (style.hasColumns() && c.isPrint()) {
-                        	FlowingColumnContainerBox cont = (FlowingColumnContainerBox) child;
+                            FlowingColumnContainerBox cont = (FlowingColumnContainerBox) child;
                             cont.setOnlyChild(c, new FlowingColumnBox(cont));
                             cont.getChild().setStyle(style.createAnonymousStyle(IdentValue.BLOCK));
                             cont.getChild().setElement(element);

openhtmltopdf-core/src/main/java/com/openhtmltopdf/layout/FloatManager.java

@@ -37,8 +37,8 @@
  * non-floated (block) boxes.
  */
 public class FloatManager {
-    private static final int LEFT = 1;
-    private static final int RIGHT = 2;
+    public static final int LEFT = 1;
+    public static final int RIGHT = 2;
 
     /* Lazily created for performance. */
     private List<BoxOffset> _leftFloats = Collections.emptyList();
@@ -124,7 +124,7 @@ private void position(CssContext cssCtx, BlockFormattingContext bfc,
         }
     }
 
-    private List<BoxOffset> getFloats(int direction) {
+    public List<BoxOffset> getFloats(int direction) {
         return direction == LEFT ? _leftFloats : _rightFloats;
     }
 
@@ -435,10 +435,10 @@ public void performFloatOperation(FloatOperation op) {
         performFloatOperation(op, getFloats(RIGHT));
     }
 
-    private static class BoxOffset {
-        private BlockBox _box;
-        private int _x;
-        private int _y;
+    public static class BoxOffset {
+        private final BlockBox _box;
+        private final int _x;
+        private final int _y;
 
         public BoxOffset(BlockBox box, int x, int y) {
             _box = box;
@@ -460,8 +460,8 @@ public int getY() {
     }
 
     private static class BoxDistance {
-        private BlockBox _box;
-        private int _distance;
+        private final BlockBox _box;
+        private final int _distance;
 
         public BoxDistance(BlockBox box, int distance) {
             _box = box;

openhtmltopdf-core/src/main/java/com/openhtmltopdf/newtable/TableBox.java

@@ -366,16 +366,8 @@ private int layoutRunningFooter(LayoutContext c) {
     }
 
     private boolean isNeedAnalyzePageBreaks() {
-        Box b = getParent();
-        while (b != null) {
-            if (b.getStyle().isTable() && b.getStyle().isPaginateTable()) {
-                return false;
-            }
-
-            b = b.getParent();
-        }
-
-        return true;
+        Box b = findAncestor(bx -> bx.getStyle().isTable() && bx.getStyle().isPaginateTable());
+        return b == null;
     }
 
     private void analyzePageBreaks(LayoutContext c) {